Counting each guest-visitation as a separate instance makes sense to me.
On one hand, the hosts will provide certain things for each guest. Invitations, individual decorations, etc. It's not like Rose & Billy can skimp on their flower budget because Marcie & John had nice bouquets at their wedding last month.
On the other hand, each guest will bring their own gift. In case of a themed wedding, they will probably buy something for that specific occasion.
On one hand, the hosts will provide certain things for each guest. Invitations, individual decorations, etc. It's not like Rose & Billy can skimp on their flower budget because Marcie & John had nice bouquets at their wedding last month.
On the other hand, each guest will bring their own gift. In case of a themed wedding, they will probably buy something for that specific occasion.